P157400 - P157400 Power Supply Equipment Fault
P157400 Power Supply Equipment Fault - Technical Specification Document
### H3 Fault Depth Definition
P157400 Power Supply Equipment Fault refers to the situation where the vehicle's control unit identifies abnormal signals or physical disconnections in the external grid power supply link during the AC charging process. This fault code involves monitoring the power transmission status between the On-Board Charger (OBC) and external energy, primarily acting on the voltage input detection loop within the power management system. When the onboard control system attempts to establish a connection with the AC grid and verify the effectiveness of energy supply, if the core power supply nodes cannot maintain a normal level state, the system determines this as Power Supply Equipment Fault. This fault directly affects the vehicle's logic for receiving and converting AC energy, belongs to abnormal warning in high/low voltage interface parts of the vehicle electrical architecture, reflecting damaged integrity of interaction between control unit and external power source.
### H3 Common Fault Symptoms
Under vehicle operation status, when triggering P157400 diagnostic code, users can perceive the non-operational state of power supply equipment through the following intuitive phenomena:
- Unable to Perform AC Charging: After connecting to a standard AC charging pile or household socket, the BMS control unit refuses to start the charging process, and the instrument panel shows the charging icon not lit or flashing red warning.
- Charging Status Locked: When the vehicle power management system detects invalid input signals, it may temporarily disable the charging port, causing that even if the user removes the vehicle, the function cannot be restored immediately and requires system reset.
- Energy Transmission Interrupted Feedback: During the initialization stage of performing the AC charging process, the instrument panel or central control screen will pop up a prompt message regarding power supply equipment abnormalities, and subsequent battery replenishment operations cannot be performed.
### H3 Core Fault Cause Analysis
According to diagnostic data logic, the root causes of P157400 can be divided into three potential failure modes across hardware components, wiring/connectors, and controller logic:
- Hardware Component Failure: Mainly refers to physical performance degradation or internal component damage of external AC charging devices, unable to output standard-compliant AC energy; Or On-Board Charger (OBC) internal high-voltage input module appears short circuit, open circuit or critical components such as rectifier bridge fail, leading to inability to receive external energy.
- Wiring and Connector Connection Abnormalities: Involving physical transmission path of power input, including cable harnesses from charging pile to vehicle existing breakage, aging damage, or male/female plug at AC charging interface not tight enough, excessive contact resistance, causing signal attenuation or interruption during transmission.
- Controller Logic Judgment Intervention: Voltage monitoring circuit of vehicle-side control unit (such as BMS or CCS) drifts, or instantaneous misjudgment occurs when processing external input signals, although hardware is normal but fails to correctly identify effective voltage signals.
### H3 Technical Monitoring and Trigger Logic
The triggering of the fault code follows strict temporal monitoring logic, with its determination process based on preset electrical parameter thresholds and timing conditions:
- Monitoring Target: The system monitors real-time AC Voltage Input signal amplitude and status at the AC charging input end.
- Condition Setting: Monitoring is conducted only when performing AC Charging Process, and during a specific control instruction activation period.
- Trigger Logic and Determination Conditions:
- System first waits for operator or external equipment to close S2 switch, establishing detection link.
- After S2 switch is closed, the electronic control unit enters a predefined time window for voltage sampling.
- If within this specified time, monitoring circuit has not detected AC Voltage Input (i.e., sampled value is below system start threshold), then fault determination is established.
- Data Retention Constraints: Diagnostic conditions strictly depend on physical existence of AC Voltage Input, ensuring vehicle only allows high voltage power-up after confirming external grid supply validity, preventing high voltage mis-activation risk in passive state.
Cause Analysis According to diagnostic data logic, the root causes of P157400 can be divided into three potential failure modes across hardware components, wiring/connectors, and controller logic:
- Hardware Component Failure: Mainly refers to physical performance degradation or internal component damage of external AC charging devices, unable to output standard-compliant AC energy; Or On-Board Charger (OBC) internal high-voltage input module appears short circuit, open circuit or critical components such as rectifier bridge fail, leading to inability to receive external energy.
- Wiring and Connector Connection Abnormalities: Involving physical transmission path of power input, including cable harnesses from charging pile to vehicle existing breakage, aging damage, or male/female plug at AC charging interface not tight enough, excessive contact resistance, causing signal attenuation or interruption during transmission.
- Controller Logic Judgment Intervention: Voltage monitoring circuit of vehicle-side control unit (such as BMS or CCS) drifts, or instantaneous misjudgment occurs when processing external input signals, although hardware is normal but fails to correctly identify effective voltage signals.
### H3 Technical Monitoring and Trigger Logic
The triggering of the fault code follows strict temporal monitoring logic, with its determination process based on preset electrical parameter thresholds and timing conditions:
- Monitoring Target: The system monitors real-time AC Voltage Input signal amplitude and status at the AC charging input end.
- Condition Setting: Monitoring is conducted only when performing AC Charging Process, and during a specific control instruction activation period.
- Trigger Logic and Determination Conditions:
- System first waits for operator or external equipment to close S2 switch, establishing detection link.
- After S2 switch is closed, the electronic control unit enters a predefined time window for voltage sampling.
- If within this specified time, monitoring circuit has not detected AC Voltage Input (i.e., sampled value is below system start threshold), then fault determination is established.
- Data Retention Constraints: Diagnostic conditions strictly depend on physical existence of AC Voltage Input, ensuring vehicle only allows high voltage power-up after confirming external grid supply validity, preventing high voltage mis-activation risk in passive state.
diagnostic code, users can perceive the non-operational state of power supply equipment through the following intuitive phenomena:
- Unable to Perform AC Charging: After connecting to a standard AC charging pile or household socket, the BMS control unit refuses to start the charging process, and the instrument panel shows the charging icon not lit or flashing red warning.
- Charging Status Locked: When the vehicle power management system detects invalid input signals, it may temporarily disable the charging port, causing that even if the user removes the vehicle, the function cannot be restored immediately and requires system reset.
- Energy Transmission Interrupted Feedback: During the initialization stage of performing the AC charging process, the instrument panel or central control screen will pop up a prompt message regarding power supply equipment abnormalities, and subsequent battery replenishment operations cannot be performed.
### H3 Core Fault Cause Analysis
According to diagnostic data logic, the root causes of P157400 can be divided into three potential failure modes across hardware components, wiring/connectors, and controller logic:
- Hardware Component Failure: Mainly refers to physical performance degradation or internal component damage of external AC charging devices, unable to output standard-compliant AC energy; Or On-Board Charger (OBC) internal high-voltage input module appears short circuit, open circuit or critical components such as rectifier bridge fail, leading to inability to receive external energy.
- Wiring and Connector Connection Abnormalities: Involving physical transmission path of power input, including cable harnesses from charging pile to vehicle existing breakage, aging damage, or male/female plug at AC charging interface not tight enough, excessive contact resistance, causing signal attenuation or interruption during transmission.
- Controller Logic Judgment Intervention: Voltage monitoring circuit of vehicle-side control unit (such as BMS or CCS) drifts, or instantaneous misjudgment occurs when processing external input signals, although hardware is normal but fails to correctly identify effective voltage signals.
### H3 Technical Monitoring and Trigger Logic
The triggering of the fault code follows strict temporal monitoring logic, with its determination process based on preset electrical parameter thresholds and timing conditions:
- Monitoring Target: The system monitors real-time AC Voltage Input signal amplitude and status at the AC charging input end.
- Condition Setting: Monitoring is conducted only when performing AC Charging Process, and during a specific control instruction activation period.
- Trigger Logic and Determination Conditions:
- System first waits for operator or external equipment to close S2 switch, establishing detection link.
- After S2 switch is closed, the electronic control unit enters a predefined time window for voltage sampling.
- If within this specified time, monitoring circuit has not detected AC Voltage Input (i.e., sampled value is below system start threshold), then fault determination is established.
- Data Retention Constraints: Diagnostic conditions strictly depend on physical existence of AC Voltage Input, ensuring vehicle only allows high voltage power-up after confirming external grid supply validity, preventing high voltage mis-activation risk in passive state.